Beijing: China today described as "common practice" one of its submarines using Colombo port in Sri Lanka as a halt on way to join the PLA's naval anti-piracy escort missions in Somalia.

Reacting to reports that the Chinese submarine's visit to Colombo demonstrated China's flexing its muscles in the Indian Ocean, Chinese military spokesman, Col Geng Yansheng told a media briefing here that "on way to the escort area, the People's Liberation Army (PLA) submarine anchored at Colombo".

"What needs to be pointed out that it is common practice for navies of all countries to have their submarines and ships managed at certain intervals at ports," he said.

China has invested a great deal in port infrastructure including Colombo and Hambantota ports which evoked concerns in India that they could be used for military purposes.

Sri Lanka however asserts that they are meant for servicing international shipping lanes.